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Summary of the impact

University of Bristol research has played an important role in shaping
local, national and global suicide prevention initiatives. The consequent
reductions in suicide rates have been substantial and many hundreds of
lives have been saved thanks to this research.

The scope and scale of the impact has ranged from shaping World Health
Organisation (WHO) strategy on preventing suicides by pesticide poisoning,
informing national legislation on limiting access to the means of suicide
in several countries (e.g. analgesics in the UK — 1000 fewer suicides
between 2008 and 2013), informing guidelines on the responsible reporting
of suicide for the UK media, and developing highly successful prevention
measures at the Clifton Suspension Bridge, a suicide site in Bristol (30
fewer suicides between 2008 and 2013).

Underpinning research

Each year, suicide accounts for 5,000 deaths in the UK and one million
deaths worldwide. In 1994 University of Bristol (UoB) researchers carried
out the first systematic review of suicide prevention strategies [1]; they
identified that restricting access to commonly used, highly lethal methods
of suicide is one of the few effective approaches to suicide prevention
strategies. This is because the risk of death varies enormously depending
on the method used in a suicide attempt. Following an overdose of
paracetamol and most antidepressants it is under 1%; after taking as
little as a tablespoonful of the toxic weed-killer paraquat it is over
70%. The risk rises to over 95% in people who jump from high structures
such as the Clifton Suspension Bridge in Bristol. Most people who survive
a suicide attempt, even one using a high-lethality method, do not make a
repeat attempt.

The researchers' seminal review led to a series of studies, many led by
the UoB, to clarify the factors that influence people's choice of suicide
method [2], the key methods of suicide used in the UK and internationally
[3,9], which methods were likely to respond to being restricted [4,5,9],
and evidence of the effectiveness of such approaches [5,6,7].

Research underpinning this impact included: (i) qualitative interviews
(led by Biddle, Donovan and Gunnell, in collaboration with University of
Taipei) with people who have survived high lethality suicide attempts in
order to better understand their choice of suicide method [2,11]; (ii)
evaluations (using natural experimental designs) of specific approaches
aimed at reducing suicide by restricting access to methods such as
pesticides and analgesics (UoB, Oxford and Edinburgh leads) [5-7,9,12];
(iii) systematic reviews [1,3,9] and (iv) collaboration with industry
(Syngenta, the manufacturer of paraquat and other pesticides) to evaluate
how a new formulation of paraquat affected death rates following
self-poisoning with paraquat (Gunnell, epidemiology lead) [8].

This research has been complemented by systematic reviews of the evidence
concerning use of specific methods of suicide (pesticides, hanging,
firearms, paracetamol and the painkiller co-proxamol) — how common they
are, how preventable they are and death rates [3,9].

Key findings of the research:

Pesticide self-poisoning accounts for approximately one third of
global suicides [3].

Bans on toxic pesticides can have a profound impact on method-specific
and overall suicide rates. A natural experimental evaluation of bans on
toxic pesticides in Sri Lanka identified a halving of suicides following
the bans [5].

In-depth qualitative studies with survivors of near-lethal suicide
methods in the UK and Taiwan reveal that news media reporting informed
their choice of suicide method [2,11].

Preventive barriers on the Clifton Suspension Bridge led to a halving
of jumping suicides, with no substitution to other sites in Bristol
[6,10].

Bans on co-proxamol have resulted in a reduction in its use for
suicide with no evidence of major substitution to other pain killers
[7,12].

Names of key University of Bristol researchers:
Professor David Gunnell (Professor of Epidemiology), University of
Bristol, 1993-present.
Professor Jenny Donovan (Professor of Social Medicine), University of
Bristol 1990-present.
Dr Lucy Biddle (Lecturer in Medical Sociology), University of Bristol
1999-present.
Ms Olive Bennewith (Research Associate) University of Bristol 1998-2012.

[10] Gunnell (PI), Bennewith (co-investigator) (2005-6) The effect of
barriers on the Clifton Suspension Bridge, England on local patterns of
suicide: implications for prevention. American Foundation for
Suicide Prevention $45,000.

[11] Gunnell (PI), Donovan, Biddle (co-investigators). (2006-9) What
influences the decision to use hanging as a means of suicide? A
qualitative study of people who have survived a nearly lethal suicide
attempt. Department of Health £111,319.

[12] Gunnell (PI), Donovan (co-investigator) (2007-11) A multi-centre
programme of clinical and public health research in support of the
National Suicide Prevention Strategy for England. Department of
Health (NIHR) £1,012,247.

Details of the impact

UoB research findings have influenced local, national and international
policymakers and health organisations, including the WHO, and have
resulted in the implementation of public health measures to restrict
access to specific suicide methods, as well as in curtailing news
reporting of these methods. Implementation of these approaches has
resulted in significant reductions in suicides.

Local research and its wider impact
UoB research led to the construction of effective barriers on the Clifton
Suspension Bridge, Bristol. Evaluation of the impact of these barriers on
suicide in Bristol indicates that they have prevented over 60 suicides by
jumping (1998-2012): deaths from the bridge declined from eight per year
(1994-98) to four per year (1998-2003) [6], with further reductions to
three per year in (2008-11). An estimated 30 fewer suicides occurred in
2008-13 as a result of the barriers [a]. This research has been used to
inform the planned introduction of prevention barriers at the Golden Gate
Bridge, USA (a process that has included consultation with Gunnell in 2006
during the planning of the barriers), and at other sites [b,c]. The
Department of Health (England) used the research findings in their Impact
assessment of the National Suicide Prevention Strategy [d]. The Bristol
research on preventing suicides by jumping has also been used to inform
position statements from important NGOs on this issue, e.g. the National
Suicide Prevention Lifeline (USA) statement on preventing suicide from
bridges.

Paracetamol and Co-proxamol in the UK
The pain killers paracetamol and co-proxamol accounted for almost half of
all the UK's overdose suicide deaths in the 1990s. UoB work on method
restriction [1] and the relationship between paracetamol availability,
pack size and mortality following paracetamol overdose [4] has contributed
to policies to restrict paracetamol pack size. Subsequent evaluative
research (with Oxford (lead) and Manchester) showed that restrictions in
the UK led to reductions in paracetamol deaths and liver transplantation
(estimated 765 fewer deaths in 1999-2009; this equated to 400 fewer in
2008-13[e]). Similarly, UoB's collaborative work with Oxford (lead) and
Manchester on the impact of co-proxamol withdrawal [7] demonstrated that
there have been 600 fewer co-proxamol suicides since its withdrawal
(2005-10).

Impact on countries' national policies
UoB research has materially influenced recommendations in national policy
documents. For example: The 2012 National Suicide Prevention Strategy for
England Preventing Suicide in England: a cross-government outcomes
strategy to save lives includes citations concerning prevention of
suicide by hanging and bridge jumping [f]; Ireland's 2000 Strategy Reach
Out (hanging), the 2012 USA National Strategy for Suicide
Prevention (pesticide poisoning) [g]; and the Canadian Institute of
Health Economics report Means Restriction for Suicide Prevention
(pesticides, paracetamol and coproxamol).

Global impact
UoB-led research on pesticide poisoning has been used widely by the WHO to
inform priorities for prevention in both global and regional (Western
Pacific) suicide prevention documents [h,i]. The research, including that
carried out in collaboration with colleagues in the South Asian Clinical
Toxicology Research Collaboration (SACTRC), encouraged the WHO to respond
to the global problem of pesticide suicides. Gunnell was a member of the
WHO advisory group and wrote an editorial to disseminate the work jointly
with the WHO leads for the strategy. Since the publication of these
documents, the Registrar of Pesticides in Sri Lanka has banned paraquat,
one of the most toxic pesticides ingested by humans; and China, where
pesticides account for two thirds of all suicides in rural areas, has
banned over 20 highly toxic pesticides (see: http://www.reach24h.com/en/news-a-events/item/439-production-ban-on-22-highly-toxic-pesticides.html).
Bans have also been introduced in Korea, Europe and India. Bristol researchers'
evaluation of bans on the most toxic pesticides in Sri Lanka indicated
that they resulted in 19,769 fewer suicides in 1996-2005 as compared with
1986-95 [2]. Based on these estimates, recent bans will have resulted in
many thousands of fewer suicides globally, as there are an estimated
370,000 pesticide suicides worldwide every year [3]. UoB researchers
worked with the company Syngenta to evaluate the impact of an improved
formulation of paraquat on case-fatality. It was shown that such new
formulations failed to substantially reduce case-fatality and imports of
paraquat were subsequently restricted in Sri Lanka [8].

Working with the mass media
UoB's work on suicide has informed the revised media guidelines produced
by the Samaritans (2013) and was used in briefings given to major national
news and media organisations (including ITV and the BBC). Gunnell met with
national newspaper editors in Parliament (organised by Madeleine Moon MP,
30 Jun 2009), the Press Complaints Commission (London, 20 Jan 2011), the
Evening Post (Bristol, 21 Dec 2011) and BBC, S4C and ITV and other news
agencies in Wales (Cardiff, 4 Dec 2012) to discuss their reporting of
suicide methods and to urge caution in describing suicide methods,
particularly those that are novel, highly lethal and readily accessible
such as those that have led to rises in suicide in some countries in East
Asia. The Samaritans used our research on the impact of their proactive
approach to advise the press on how to report (and when not to report)
novel methods of suicide in their submission to the Leveson Inquiry [j]

Additional benefits to society, the economy, and the police and health
services
It is estimated that for every suicide, six people are seriously affected,
so the overall fall in suicide rates reduces the emotional toll on friends
and family, who may require bereavement and counseling services and time
off work due to the bereavement (which also carries a cost to the
economy). The reduced toxicity of drugs / poisons taken in overdose will
also result in cost savings through reduced use of intensive care beds and
shortened hospital admissions. These are real and substantial benefits but
the actual cost saving is difficult to quantify.

Sources to corroborate the impact

[a] Sources to corroborate impact of research on suicide by
jumping/suicide from the Clifton Suspension Bridge: Data from Mr Dave
Anderson, Bridgemaster, Clifton Suspension Bridge Suicide showing
reduction in suicide; [reference [6], page 2 includes data on deaths
before the installation of the barrier].

[b] The use of barriers on the Clifton Suspension Bridge has used to
inform construction of a bridge barrier for the Archway Bridge, London
(email seeking advice)

[e] Evidence of the impact of co-proxamol and paracetamol restrictions on
reducing suicides. Reference [7] and Hawton et al Long term effect of
reduced pack sizes of paracetamol on poisoning deaths and liver transplant
activity in England and Wales: interrupted time series analyses BMJ2013;346:f403
doi: 10.1136/bmj.f403

[k] Further evidence of impact of research on media reporting of suicide
methods: Letter from The Samaritans summarising the contribution made in
relation to working with the media to improve reporting of suicide.